select IFNULL(c.nodeCount,0) + IFNULL(c.phyCount,0) as totalCount from ( select count(*) nodeCount, (select count(*) from rn_base a join rn_ext_systeminfo b on a.id = b.nodeId where (a.subType = 'VIRTUAL' or a.subType = 'PHYSICAL')) phyCount from rn_base a join rn_ext_vir_instance b on a.id = b.nodeId where a.subType = 'VIR_INSTANCE' ) c